宏观与微观相结合是化学学科的思维特点．

将函数f（x）=sin2x的图象向右平移φ（0＜φ＜ $\frac{\pi }{2}$ ）个单位后得到函数g（x）的图象，若函数g（x）在区间0， $\frac{\pi }{3}$ 上单调递增，则φ的取值范围是（   ）

少先队员每人做好事的件数一定，做好事的总件数与做好事的少先队员人数成正比例．

若正数a，b，c满足a+b+c=1，则$\frac{1}{3a+2}$+$\frac{1}{3b+2}$+$\frac{1}{3c+2}$的最小值为____ 

— A       gunman killed 17 people at a high school in the state of Florida on February 14th, 2018 and the American president Donald Trump signals support for raising age for gun buying.

—        terrible news!